VIRIDIANS STREPTOCOCCI

Question 1

Are oropharyngeal commensals:

Answer 1

viridans streptococci

Question 2

Normal microbiota of the URT, female genital tract and GIT:

Answer 2

viridans streptococci

Question 3

Viridans streptococci are also known as:

Answer 3

alpha-prime streptococci

Question 4

Causes three main types of infection:

Answer 4

1. dental infections
2. endocarditis
3. abscesses

Question 5

Most common cause subacute bacterial endocarditis (SBE):

Answer 5

viridans streptococci

Question 6

Virulence factors:

Answer 6

“CACE”
capsule
adhesins
cytolysin
extracellular dextran

Question 7

Enhance attachment to host cell surfaces, such as cardiac endothelial cells or tooth surfaces in the case of dental carriers:

Answer 7

extracellular complex polysaccharide

Question 8

Laboratory test:

Answer 8

bile insoluble
optochin (R)
no growth in 6.5% NaCl
LAP (+)
PYR (-)

Question 9

5 Groups of Viridans:

Answer 9

“BAMMS”
1. S. bovis group
2. S. anginosus group
3. S. mitis group
4. S. mutans group
5. S. salivarius group

Question 10

S. mitis group:

Answer 10

“I PaGoMiCr PO(z)”
S. infantis
S. parasanguis
S. gordonii
S. mitis
S. cristatus
S. peroris
S. oralis

Question 11

S. mutans group:

Answer 11

“SoMu”
S. sobrinus
S. mutans

Question 12

S. salivarius group:

Answer 12

“SaVeT”
S. salivarius
S. vestibularis
S. thermophilus

Question 13

S. bovis group:

Answer 13

“I GAE”
S. infantarius
S. gallolyticus
S. alactolyticus
S. equinus

Question 14

S. anginosus group:

Answer 14

“CAI”
S. constellatus
S. anginosus
S. intermedius

Question 15

Laboratory tests:

Answer 15

1. growth in bile esculin medium
2. 6.5% NaCl (nutrient broth base) test
3. PYR test
4. Penicillin test

Question 16

Esculin hydrolysis test for the cleavage of a glycoside:

Answer 16

growth in bile esculin medium

Question 17

Reagent of bile esculin:

Answer 17

esculin + 1-4% bile salt

Question 18

Bile esculin test (+) result:

Answer 18

black color complex in the agar within 48 hours

Question 19

6.5% NaCl test (-) result:

Answer 19

no growth

Question 20

PYR test result:

Answer 20

negative

Question 21

Penicillin test result:

Answer 21

susceptible

Question 22

Most commonly isolated viridans:

Answer 22

S. mutans group

Question 23

Viridans that possesses the group D antigen:

Answer 23

S. bovis and enterococci

Question 24

Often isolated in blood cultures of individuals with GI carcinoma:

Answer 24

Bovis group (S.equinus)

Question 25

Lancefield antigens of anginosus:

Answer 25

group A, C, F, G, or N

Question 26

Colonies are surrounded by a very small zone of no hemolysis and then a wider zone of B-hemolysis:

Answer 26

alpha-prime hemolysis/wide zone hemolysis